Testing device



E. G. THOMAS TESTING DEVICE June 20, 1933.

Original Filed April 28, 1921 2 Sheets-Sheet l amounted; [award 6.7/70/7705 E. G. THOMAS TESTING DEVICE June 20, 1933.

Original Filed April 28, 1921 2 Sheets-Sheet 2 Patented June 20, 1933UNITED STATES PATENT OFFICE.

EDWIlBD G. THOMAS, OF TOLEDO, OHIO, ASSIGNOR TO TOLEDO SCALEMANUFACTURING COMPANY, OF TOLEDO, OHIO, A CORPORATION OF NEW JERSEYTESTING DEVICE Original application filed April 28, 1921, Serial No.465,134,and in Canada October 5, 1922. Divided and this applicationfiled November 12, 1927.

This application is a division of my application Ser. No. 465,134, filedApril 28, 1921, testing devices.

This invention relates to testing devices, and particularly to devicesfor testing the .weight per unit of length of a strip of fabric or othermaterial. It is desirable that coated fabrics and similar products be ofuniform weight, and calendering means are commonly provided with meanswhereby the weight of the coating may be increased or decreased. It isvery difiicult, however, to detect small variations in the weight ofcoating until a considerable quantity of the material has been coatedand is available for weighing, and failure to detect and correct suchvariations often results in considerable losses.

The principal object of my invention is to provide a device by means ofwhich variations in the weight of a product may be detected as it passesfrom the machine.

Another object is to provide automatic means for indicating suchvariations.

Still another object is to provide means for controlling the machine bywhich the product is made or supplied.

Other objects and advantages will be apparent from the followingdescription, in which reference is bad to the accompanying drawingsillustrating preferred embodiments of my invention and wherein similarreference numerals designate similar parts throughout the several views.

In the drawings 2- Figure 1 is an isometric view of one form of a deviceembodying some of the features of my invention;

Figure 2 is a rear elevation thereof;

Figure 3 is a perspective view of a part of the device embodying furtherfeatures of my invention: and

Figure 4 is a diagrammatic view of a system of wiring which may beemployed in connection with the device shown in Figure 3.

Referring to the drawings in detail and particularly to Figures 1 and 2,the frame of the apparatus is shown as consisting principally of basemembers 1 and 2 and a plu- Serial Ne. 232,795.

rality of uprights which support the working parts of the device. Thisparticular form of frame is shown by way of example only.

Supported by the uprights 3, 4, 5 and 6 at the ends of the base members1 and 2 are parallel rollers 7 and 8 over which the fabric or othermaterial may be passed, as shown in the drawings. Other uprights 9 and10 rise from the central portions of the base members 1 and 2, andprojecting from the upright 9 is a fulcrum bracket 11 carrying a groovedbearing 13, while a grooved bearing 14 is supported upon the upper endof the upright 10. The bearing 13 rockably supports the knife edge pivot15 of a lever 16, while the bearing 14 rockably supports the knife edgepivot 17 of a lever 18. The levers l6 and 18 are rigidly connected bymeans of a bar which lies considerably below a plane tangent to theupper surfaces of the rollers 7 and 8. A third roller 20 is supported bythe levers 16 and 18 so that it may move from a position with its uppersurface above the plane tangent to the upper surfaces of the rollers 8and 7 to a position with its upper surface below such plane.

Supported upon the upper end of the standard 9 is a weighing andindicating device, which I have illustrated as of the automatic pendulumweighing scale type.

The base 21 of the weighing scale supports a lever 22, the nose of whichextends into a housing 28 and is connected to a pendulum 24 in themanner well known in the art. An indicating hand 25 is fixed to thependulum and swings in the upper fan-shaped part 26 of the housing 23.The fan-shaped part of the housing contains a suitable chart 27 whichco-operates with the hand 25, both the chart and the hand being visiblethrough a window in the housing. The chart is pref? erably of thepredetermined weight type, a single point being marked and the wordsUnder and ver respectively being placed at the left and right side ofthe predetermined point. The scale may, if desired, be provided with aduplicate indicating device 28 which is visible from the other side ofthe housing. When the nose of the lever is depressed the pendulum swingsupwardly,

can

offering increasing resistance to the force depressing the nose of thelever, and the hand at the same time swings across the chart.

The weighing scale so far described is not per se of my invention and isnot per se claimed herein, and the substitution of other types ofweighing scales for the type illustrated is within the scope of thepresent invention. I have, therefore, illustrated and described the typeshown with such particularity only as will suffice for a clearunderstanding of its relation to the other elements of my invention.

Rigidly connected to the main lever 22 of the scale (in a posit-ioncorresponding to that occupied by the tare beam of a scale for ordinaryweighing) is a beam 29, the left end of which extends considerablybeyond the nose of the lever. This end of the beam 29 is connected tothe end of the lever 16 by means of a link 30, the parts being soarranged and adjusted that when the lever 16 is sufficiently depressedto bring the upper side of the roller 20 into tangency with the planewhich is tangent to the upper surfaces of the rollers 7 and 8 theindicator will register with the predetermined mark.

The beam 29 carries a poise 31 which, when there is a load on the roller20, may be moved to a position to balance the scale with the roller 20in tangency with the plane tangent to the rollers 7 and S and theindicator hand in registration with the predetermined point on thechart.

The action of the device is steadied by means of a dash pot 32, andmovement of the lever mechanism is limited by means of stops 33.

If a strip of fabric be laid upon the rollers and the poise 31 be movedto a position to bring the hand 25 into registration with apredetermined point, the rollers 7, 20 and 8 will be tangent to the sameplane. Approximately half of the strip between the rollers 7 and S willbe supported by the roller 20 and the proportion of this part of thestrip carried by the roller 20 will not be appreciably changed byincreasing or decreasing the tautness of the strip. If the weight of thestrip be uniform the load on the roller 20 will be increased only whenthe tension on the strip is reduced sufficiently to allow the sagbetween the rollers to lengthen the part of the strip supported by themand the load will be decreased only when the tension is increasedsufficiently to shorten the part of the strip between the rollers 7 and8. In practice the tension on the fabric is very great as compared withthe weight of the fabric, so that the strip is always taut, and noappreciable change in load results from small changes in tension.

Since the roller 20 is neither above nor below the rollers 7 and 8,increasing the tension tends neither to lift the strip from the roller20 nor to force the roller downwardly, so that the load on the roller ismerely the weight of that portion of the fabric supported thereby.

Since the roller 20 supports half the portion of the strip between therollers 7 and 8, it is evident that any increase in the weight of thatpart of the strip will depress the roller and any decrease will allow itto swing upwardly. Either movement of the roller will cause the hand toswing away from the central point on the chart and thus indicate thechange in weight.

By passing a strip of material over the rollers as it comes from aealendering or other machine any change in the weight of the strip perunit of length may be at once detected and the necessary adjustments tobring the product back to its original weight may be promptly made.

' In Figures 3 and l I have shown a further development of my inventionwhereby the adjustment of the machine supplying the strip of materialmay be controlled automatically. The mechanism so far described is alsoemployed in this development of the invention, being placed as before inposition to test the weight of the material as it comes from the machineby which it is supplied (in this example shown as a calendaring machinewhich consists essentially of a frame 40 supporting a series ofadjustable rollers 41, 42, \Vhen a machine of the type illustrated isemployed for applying rubber to fabric, the rubber may be formed into asheet by passing it between the upper rollers 41 and 42, the rubber fromthe mass B and fabric from the roll F thence passing together betweenthe rollers 42 and 43. whereby the rubber forced into the fabric. Thethickness and hence the weight of the sheet of rubber is determined bythe spacing of the rollers ll and 42. For the purpose of automaticallyregulating the spacing of the rollers l1 and 42 I have provided areversible motor 44 controlled by switches which are operated bymovement of the indicating hand 25 from the central position.

The system of control may best be explained by reference to Figure at,from which it will be seen thatmovement of the indicator hand to theleft closes the switch 45 and energizes the magnet 4E6, thereby swingingthe arm 47 to the left and closing the contacts 48 and the contacts 49and causing the current to flow from the generator G through the motorarmature M and through the field in one direction. Movement of the hand25 to the right closes the switch 51 and energizes the magnet 52,thereby swinging the arm 47 to the right and closing the contacts 52)and the contacts 54 and causing the current to flow through the motorarmature and through the field in the opposite direction.

From the foregoing it will be apparent that so long as the weight of thecoated fabric and therefore the load on the roller 20 remains uniform,the motor 44 will remain at rest, but if the fabric runs light and thehand 25 swings to the left the motor will be actuated and the armaturewill be turned in one direction, and if the fabric runs heavy the motorwill be actuated with the polarity of the field reversed and thearmature will be turned in the opposite direction.

The upper roller 41 is supoprted by cross heads 55 slidably moutned inthe frame 40 of the coating machine and movable by means of worm gearingconnected to the motor 44 and so arranged that when the fabric runslight the upper roller 41 is raised and the space between the rollers 41and 42 is increased, and when the fabric runs heavy the space betweenthe rollers 41 and 42 is decreased. The substantial uniformity of theproduct is thus insured.

In cases in which it is desired that the in dication be visible from adistance a red lamp 60 may be interposed in the circuit, which is closedwhen the hand 25 is swung to the right by reason of an increase inweight per unit of area of the material, and a green light 61 may beinterposed in the circuit, which is closed when the hand 25 swings tothe left by reason of the decrease in the weight per unit of area of thematerial, and circuits containing lamps of different colors may, ofcourse, be employed in cases in which the automatic control mechanism isnot used.

While it will be apparent that the illus trated embodiments of myinvention herein disclosed are well calculated to adequately fulfill theobjects primarily stated, it is to be understood that the invention issusceptible to variation, modification and change within the spirit andscope of the subjoined claims.

Having described my invention, I claim:

1. In a device of the class described, in combination, means fordelivering a sheet of material, said delivering means including meansfor varying the weight per unit of length of such. material, means fordetecting variations in the Weight per unit of length as such materialis delivered, and means controlled by said detecting means forcontrolling said varying means.

2. In a device of the class described, in combination, means fordelivering a sheet of material, said delivering means including meansfor varying the weight per unit of length of such material, means fordetecting variations in the Weight per unit of length as such materialis delivered, said detecting means including a pair of supports for themoving sheet of material, means engaging the mate rial between saidsupports for detecting changes in its weight per unit of length, saiddetecting means being substantially unaffected by the tautness in thematerial, and means controlled by said detecting means for controllingsaid varying means.

"engagingsaid pair of supports, and means controlled by saidpredetermined weighing device for controlling said varying means.

4. In a device of the class described, in

combination, means for delivering a strip of material, said deliveringmeans including means for varying'the weight per unit of length of suchmaterial, means for detecting variations in the weight per unit oflength of such material as it is delivered, said detecting meansincluding a pair of supports, the upper surfaces of which lie insubstantially the same plane, a support lying between the first saidsupports and movable from a position with its upper surface above theplane of the upper surfaces of the first said supports to a positionwith its upper surface below such plane, manually adjustable means forcounterbalancing a portion of the load on said movablev support,automatic means for counterbalancing the remainder of the load, andmeans connected to said automatic means for controlling saidweight-varying means.

5. In a device of the class described, in com-- bination, means fordelivering a strip of material, means for varying the weight per unit oflength of such material, means for detecting variations in the weightper unit of length as such material is delivered, and electric meanscontrolled by said detecting means for controlling said varying means.

6. In a device of the class described, in combination, means fordelivering a strip of material, means for varying the weight per unitoflength of such material, means for detectin g variations in the weightper unit of length as such material is delivered, and electric meanscontrolled by said detecting means for controlling said varying means,said electric means comprising a reversible motor for operating saidvarying means, and means controlled by said detecting means forselectively operating said motor in reverse directions.

7. In combination apparatus for continuously producing sheet fabric, aweighing machine through which the sheetfabric is passed forautomatically detect-ing variations in the weight thereof, and meanscontrolled in response to changes in the weight of the sheet fabricbeing produced for regulating said apparatus in a manner to change thethickness of the sheet fabric produced thereby.

8. In combination apparatus for continuously producing sheet fabric, aweighing machine through which the finished fabric is passed fordetecting variations in the weight thereof and means controlled by saidweighing machine in response to deviations in the weight of the finishedfabric from a given standard for regulating the apparatus in a manner tocorrect the Weight of the fabric being produced by changing itsthickness.

9. In combination a machine for producing continuous sheets of fabric,apparatus for causing the fabric to conform to a substantially standardthickness comprising a machine for continuously Weighing a constantWidth and length of the fabric as it is produced, and means controlledby said Weighing machine for regulating said producing machine.

EDWVARD G. THOMAS.

